Disk player using a single switch in common for driving its tray and drive motor

ABSTRACT

Disclosed is a disk player using a single motor in common for driving its disk tray and optical pickup. The controlled reciprocation of the disk tray and the data-reproducing operation subsequent to withdrawal of the disk tray into the housing can be performed by the “L”-shaped guide slot made in the disk tray, the cam rod operatively connected to the “L”-shaped guide slot, and the drive switching gear assembly operatively connected to the cam rod and the first train of gears for driving the disk tray. All of these parts work together so that the single drive motor may switch and drive the first train of gears for driving the disk tray or the second train of gears for driving the optical pickup. A cam position-detecting switch is operatively connected to the cam rod for detecting arrival of the cam rod at either terminal of its travel, that is, the gear train connecting or gear train-disconnecting position.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a disk player for use inrecording and reproducing data in an optical disc or a magneto-opticaldisc such as a CD, DVD, or MD, using a switch in common for puttingdifferent drive systems in operation.

[0003] 2. Related Art

[0004] A disk player comprises a disk tray movable between the openingposition in which the disk tray appear out of the housing and theclosing position in which the disk tray enters the housing, a turn tablebearing a disk, a turn table drive, a optical pickup, a optical pickupdrive and other movable parts. Motors are allotted to the drive systemsto enable their movable parts to function as required.

[0005] JP 9-27180A, titled “Disk Player” proposes a disk drive mechanismwhich is swingable about its pivot between a horizontal position inwhich the mechanism is flush with the disk tray and an oblique positionin which the mechanism inclines downward apart from the disk tray. Thedisk drive mechanism is raised from the oblique to horizontal positionprior to the advance of the disk tray out of the casing, and it isinclined from the horizontal to oblique position posterior to thewithdrawal of the disk tray into the housing.

[0006] The disk tray has a tray rack and a tray drive gear is meshedwith this tray rack. The disk tray moves back and force according torotation of the tray drive gear. The tray drive gear is meshed with arack arranged at one end of a cam rod to move the cam rod in the leftand right directions, while making the driving mechanism to swing in theupward and downward directions. That is, the disk tray moves back andforce, and at the same time the driving mechanism swings according torotation of the tray drive gear.

[0007] Both positions the disk tray moves force to be opened and back tobe closed must be established precisely. For that purpose, a guide frameis made on the back surface of the disk tray for a boss projected fromthe cam rod to movably fit therein so that the disk tray be closed at acorrect position. The opening position of the disk tray is controlled bya limit switch for stopping the force movement.

[0008] As mentioned above, a limit switch for stopping the forcemovement of the disk tray is used to decide the opening and closingpositions of the disk tray. One object of the present invention is toprovide a disk player using a single limit switch to control preciselythe opening and closing positions of the disk tray and give signals tocommence the next motion.

SUMMARY OF THE INVENTION

[0009] To attain this object a disk player according to the presentinvention comprises: a housing; a disk tray movable between the openingposition in which the disk tray appears out of the housing and theclosing position in which the disk tray enters the housing, the disktray having a tray rack and an “L”-shaped tray guide slot, of which thelongitudinal guide slot section extends parallel to the tray rack andthe lateral guide slot section extends parallel to the front side of thedisk tray; a first train of gears for moving the disk tray back andforth between the opening and closing position, one of the first trainof gears meshing with the tray rack in the form of rack-and-pinion; amovable optical pickup; a second train of gears for moving the opticalpickup radially across the disk; a cam rod movable between the geartrain-connecting position in which the first and second trains of gearsare coupled and the gear train-disconnecting position in which the firstand second trains of gears are disconnected, the cam rod beingoperatively connected to the “L”-shaped tray guide slot; a switchingdrive gear assembly operatively connected to the cam rod for swingingbetween the gear train-connecting position and the geartrain-disconnecting position; a drive motor connected to the first trainof gears; and a cam position detecting switch operatively connected tothe cam rod for detecting arrival of the cam rod at either terminal ofits travel, the cam rod being so formed that when the first train ofgears moves the disk tray toward the opening or closing position withthe rack-and-pinion, the cam rod remains in the gear train-disconnectingposition, and that in the closing position the rack-and-pinion isdisconnected to permit the separate pinion to move the cam rod to thegear train-connecting position, making the drive switching gear assemblyswing about its drive until the first and second trains of gears areconnected to allow the drive motor to drive the second train of gearsfor moving the optical pickup while the first train of gears rotatewithout moving the disk tray.

[0010] The cam rod comprises an orthogonal, horizontal-and-verticalguide plate assembly, the horizontal guide plate having a relativelynarrow guide slot, a relatively wide guide slot, and a wide-to-narrowtransient slope, thus making the swinging drive gear assembly swingtoward the second train of gears when the axle of the swinging drivegear assembly remains in the relatively narrow guide slot, and makingthe drive switching gear assembly swing apart from the second train ofgears when the axle of the swinging drive gear assembly remains in therelatively wide guide slot.

[0011] The support member on which the second train of gears and theoptical pickup are fixed is adapted to turn about its pivot between thehorizontal position and the oblique position, and the cam rod comprisesan orthogonal, horizontal-and-vertical guide plate assembly, thevertical guide plate having an “escalator”-like slot to catch the freeend of the support member, thus making the support member turn about itspivot until the second train of gears rises to be flush with the driveswitching gear assembly when the cam rod reaches the gear trainconnecting position.

[0012] The cam position detecting switch is a snap switch fixed to thehousing at such a position that its arm may be caught by first andsecond projections of the cam rod, which first and second projectionsare so positioned that the first projection abuts on the arm of the snapswitch when the cam rod reaches the gear train-disconnecting position,and that the second projection abuts on the arm of the snap switch whenthe cam rod reaches the gear train-connecting position.

[0013] Other objects and advantages of the present invention will beunderstood from the following description of a disk drive according toone embodiment of the present invention, which is shown in accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWING

[0014]FIG. 1 is a plane view of a disk player according to oneembodiment of the present invention with its disk tray appearing out ofthe housing;

[0015]FIG. 2 is a plane view of the disk player with its disk trayentering the housing;

[0016] FIGS. 3(a) and 3(b) are plane and side views of a cam rod whichcan traverse the housing;

[0017]FIG. 4 illustrates how a first train of toothed wheels for drivingthe disk tray is coupled with a second train of toothed wheels fordriving the optical pickup through the agency of the drive-switchinggear assembly and the cam rod, which is driven rightward in the drawing;

[0018] FIGS. 5(a) and 5(b) are plane and side views of a drive-switchinggear assembly;

[0019]FIG. 6(a) is a side view of the disk player with its disk traypushed out of the housing while FIG. 6(b) is a similar side view, butshowing the disk player with its disk tray pulled in the housing;

[0020] FIGS. 7(a) and 7(b) are cross sections of the disk player takenalong the line “7(a)”-“7(a)” in FIG. 6(a), and taken along the line“7(b)”-“7(b)” in FIG. 6(b) respectively; and

[0021]FIG. 8 is similar to FIG. 4, but illustrating how the cam rod ismoved leftward from the cam rod position of FIG. 4, therebydisconnecting the first train of toothed wheels from the second train oftoothed wheels.

[0022]FIG. 9(a) is a cross section of the disk player similar to FIGS.7(a) and 7(b), but illustrating how the cam position detecting switchdetects arrival of the cam rod at the gear train-disconnecting positionwhereas FIG. 9(b) is a plane view of a fragment of the disk player,illustrating the same area and position as FIG. 9(a); and

[0023]FIG. 10(a) is a similar cross section, but illustrating how thecam position detecting switch detects arrival of the cam rod at the geartrain-connecting position whereas FIG. 10(b) is a plane view of afragment of the disk player, illustrating the same area and position asFIG. 10(a).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0024] Referring to FIG. 1, the disk player has its disk tray 1 put inopening position, in which the disk tray 1 appears from the casing 35.The disk tray 1 has a circular depression made on its upper surface foraccommodating a disk. It has a tray rack 2 and an “L”-shaped guide slot3 made on its lower surface. First and second trains of gears allottedfor driving the disk tray 1 and the optical pickup 23 respectively aremounted in the housing 35. The first train of gears can be detachablycoupled with the second train of gears via an intervening driveswitching gear assembly (FIG. 5) and a cam rod 10 (FIG. 3). The cam rod10 has its boss 5 movably fitted in the guide slot 3. The tray rack 2and associated tray drive gear 4 are combined to provide arack-and-pinion, which can move the disk tray 1 back and force when thedrive motor 6 is energized to drive the first train of gears.

[0025] When the drive motor 6 rotates the tray drive gearcounterclockwise, the disk tray 1 is made to advance a predetermineddistance, reaching the opening position (FIG. 1), and when the drivemotor 6 rotates the tray drive gear clockwise, the disk tray 1 is madeto withdraw the predetermined distance, reaching the closing position(FIG. 2). This controlled reciprocation and the data-reproducingoperation subsequent to withdrawal of the disk tray 1 in housing 35 canbe performed by the unique mechanism according to the present invention,which comprises the “L”-shaped guide slot 3, the cam rod 10 operativelyconnected to the “L”-shaped guide slot 3, and the drive-switching gearassembly 12 and 19 operatively connected to the cam rod 10 and the firsttrain of gears. All of these parts work together so as to permit thesingle drive motor 6 to switch and selectively drive the disk tray 1 orthe optical pickup 23.

[0026] As shown in FIG. 1, the “L”-shaped guide slot 3 is composed of alongitudinal slot section 7, a lateral slot section 8, and alongitudinal-to-lateral transient slot section 9. Longitudinal slotsection 7 is bent in the vicinity of its end as indicated at 30.Referring to FIG. 3, the cam rod 10 comprises an orthogonal,horizontal-and-vertical guide plate assembly. As shown in the drawing,the horizontal guide plate has cam rack 11 formed at one end on onelongitudinal side, a boss 5 standing upright close to the one end, alongitudinal guide groove 14, a projection 42 formed on the onelongitudinal side, a chamfered projection 29 formed on the otherlongitudinal side (see FIG. 3a). The guide groove 14 comprises arelatively narrow groove section 16 b, a relatively wide groove section16 a and an oblique, narrow-to-wide groove transient section 17. On theother hand, the vertical guide plate has an “escalator-like” guidegroove 15 made therein (FIG. 3b). Finally referring to FIG. 5, adrive-switching gear assembly comprises a drive-switching gear 12 and anassociated gear 19, both connected by an arm 20. The arm 20 has aprojection 32, and a stationary spring wire 33 is caught by theprojection 32, pushing the drive switching gear 12 apart from theleading gear or pickup-feeding gear 13 of the second train of gears.Thus, the drive-switching gear assembly is normally spring-biased towardthe disconnecting position in which the first train of gears for drivingthe disk tray 1 is disconnected from the second train of gears fordriving the pickup 31.

[0027] The drive-switching gear 12 has its axle 18 inserted in the guidegroove 14 of the guide rod 10. In the disconnecting position the axle 18remains in the relatively wide groove section 16 a. Therightward-movement of the cam rod 10 makes the axle 18 climb theoblique, narrow-to-wide groove transient section 17 to enter therelatively narrow groove section 16 b, thereby pushing thedrive-switching gear 12 toward the leading gear 13 of the second trainof gears, that is, the pickup-feeding gear 13 against the counterspring-bias 33 until the drive-switching gear 12 meshes with thepickup-feeding gear 13 (FIG. 4). In the connecting position thus reachedthe optical pickup 23 can be driven by the drive motor 6 through theagency of the second train of gears and an associated rack-and-pinion 27and 26. Then, the optical pickup 31 traverses the disk in its radialdirection to reproduce data therefrom.

[0028] More specifically, when the drive motor 6 drives therack-and-pinion 2 and 4 via the first train of gears to move the disktray 1 toward the opening position, first, the boss 5 of the cam rod 10follows the longitudinal slot section 7, and it climbs the bent portion30 to draw the cam rod 10 leftward. Arrival of the cam rod 10 at thefarthest left position is detected to stop the drive motor 6. Thus, thedisk tray 1 stops after traveling a predetermined distance substantiallyequal to the longitudinal slot section 7 (see FIG. 1).

[0029] Conversely when the motor 6 drives the rack-and-pinion 2 and 4 topull the disk tray 1 toward the closing position, the boss 5 of the camrod 10 follows the longitudinal slot section 7, and then the boss 5follows the lateral slot section 8 after passing thelongitudinal-to-lateral transient section 9. Then, the disk tray 1 isput in closing position (see FIG. 2), and the tray driving gear 4 leavesthe tray rack 2 to mesh with the cam rack 11 of the cam rod 10 to movethe cam rod 10 rightward as the drive motor 6 continues rotating. Thus,the boss 5 of the cam rod 10 advances in the lateral slot section 8rightward.

[0030] When the boss 5 reaches the dead-end of the lateral slot section8 to draw the cam rod 10 to the farthest right position, the axle 18 ofthe drive switching gear 12 is pulled up from the relatively wide slotsection 16 a to the relatively narrow slot section 16 b against thecounter bias-spring 33, thus making the drive switching gear assemblyswing about its pivot so that the drive-switching gear 12 moves towardthe pickup feeding gear 13.

[0031] Referring to FIGS. 6(a) and 6(b), and FIGS. 7(a) and 7(b), thetraverse holder 21 bearing the second train of gears has its tip boss 24movably fitted in the “escalator”-like guide slot 15 of the cam rod 10.As the disk tray 1 moves from the opening position to closing position,the tip boss 24 of the traverse holder 21 climes the “escalator”-likeguide slot 15, and accordingly the traverse holder 21 turns about itspivot from the inclined position (see FIGS. 6(a) and 7(a)) to thehorizontal position (see FIGS. 6(b) and 7(b)), thereby raising thesecond train of gears, particularly the pickup feeding gear 13 to beflush with the drive-switching gear 12. Thus, the pickup feeding gear 13meshes with drive switching gear 12, permitting the drive motor 6 todrive the second train of gears. Thus, the optical pickup 21 is drivenby the drive motor 6 through the agency of the rack-and-pinion 26 and 27associated with the second train of gears (see FIG. 4).

[0032] In the connecting position the optical pickup 31 moves across thedisk in its radial direction to record or reproduce data from the diskwhile the chamfered end of rack 27 continues pushing the counterchamfered end of the projection 29 of the cam rod 10, thus pushing thecam rod leftward until the drive switching gear 12 of thedrive-switching gear assembly rolls down on the narrow-to-wide transientincline 17 to leave the pick-up feeding gear 13 of the second gang ofgears as the pulling force from the spring bias 32 is applied to thedrive switching gear 12 all the time (see FIG. 8). Thus, the opticalpickup 31 stops traversing the disk.

[0033] Referring to FIGS. 9(a) and 9(b), the cam position-detectingswitch 40 is a snap switch 40 fixed to the housing 35. When the cam rod10 reaches the gear train-disconnecting position 43 (the farthest leftposition), the arm 41 of the snap switch 40 is caught by the recessformed by the cam rack 11, thus making the snap switch 40 to be thrownto one side.

[0034] Referring to FIGS. 10(a) and 10(b), when the cam rod 10 reachesthe gear train-connecting position (the farthest right position), thearm 41 of the snap switch 40 is caught by the projection 42 of the camrod 10, thus making the snap switch 40 to be thrown to the other side.

[0035] As may be understood from the above the controlled reciprocationof the disk tray and the data-reproducing operation subsequent towithdrawal of the disk tray in the housing can be performed by makingthe “L”-shaped guide slot, the cam rod and the drive-switching gearassembly work in unison, permitting the single drive motor to switch andselectively drive the disk tray or the optical pickup timely.

What is claimed is:
 1. A disk player comprising: a housing; a disk traymovable between the opening position in which the disk tray appears outof the housing and the closing position in which the disk tray entersthe housing, the disk tray having a tray rack and an “L”-shaped trayguide slot, of which the longitudinal guide slot section extendsparallel to the tray rack and the lateral guide slot section extendsparallel to the front side of the disk tray; a first train of gears formoving the disk tray back and forth between the opening and closingposition, one of the first train of gears meshing with the tray rack inthe form of rack-and-pinion; a movable optical pickup; a second train ofgears for moving the optical pickup radially across the disk; a cam rodmovable between the gear train-connecting position in which the firstand second trains of gears are coupled and the gear train-disconnectingposition in which the first and second trains of gears are disconnected,the cam rod being operatively connected to the “L”-shaped tray guideslot; a switching drive gear assembly operatively connected to the camrod for swinging between the gear train-connecting position and the geartrain-disconnecting position; a drive motor connected to the first trainof gears; and a cam position detecting switch operatively connected tothe cam rod for detecting arrival of the cam rod at either terminal ofits travel, the cam rod being so formed that when the first train ofgears moves the disk tray toward the opening or closing position withthe rack-and-pinion, the cam rod remains in the gear train-disconnectingposition, and that in the closing position the rack-and-pinion isdisconnected to permit the separate pinion to move the cam rod to thegear train-connecting position, making the drive switching gear assemblyswing about its pivot until the first and second trains of gears areconnected to allow the drive motor to drive the second train of gearsfor moving the optical pickup while the first train of gears rotatewithout moving the disk tray.
 2. A disk player according to claim 1,wherein the cam rod comprises an orthogonal, horizontal-and-verticalguide plate assembly, the horizontal guide plate having a relativelynarrow guide slot, a relatively wide guide slot 16 a, and awide-to-narrow transient slope, thus making the drive switching gearassembly swing toward the second train of gears when the axle of theswinging drive gear assembly remains in the relatively narrow guideslot, and making the drive switching gear assembly swing apart from thesecond train of gears when the axle of the swinging drive gear assemblyremains in the relatively wide guide slot.
 3. A disk player according toclaim 2, wherein the support member on which the second train of gearsand the optical pickup are fixed is adapted to turn about its pivotbetween the horizontal position and the oblique position, and the camrod 10 comprises an orthogonal, horizontal-and-vertical guide plateassembly, the vertical guide plate having an “escalator”-like slot tocatch the free end of the support member, thus making the support memberturn about its pivot until the second train of gears rises to be flushwith the drive switching gear assembly when the cam rod reaches the geartrain connecting position.
 4. A disk player according to claim 1, 2 or3, wherein the cam position detecting switch is a snap switch fixed tothe housing at such a position that its arm may be caught by first andsecond projections of the cam rod, which first and second projectionsare so positioned that the first projection abuts on the arm of the snapswitch when the cam rod reaches the gear train-disconnecting position,and that the second projection abuts on the arm of the snap switch whenthe cam rod reaches the gear train-connecting position.